The present invention relates to a screw separator or a screw press separator for separating solids out of suspensions, comprising a housing and a suspension feed pipe, a liquids discharge, and an outlet for the dewatered solids.
These screw separators, often called filter screw presses, are per se known from the prior art. Screw separators have also become known in which two series-connected, separate filter screens are provided which are configured as strainer baskets. The first strainer basket serves as a liquid filter for separating out the bulk of the liquid portion while the downstream press basket comprises the solids compacted to form a slug. The pressure prevailing in the press basket is considerably increased such that maximum stresses occur there.
The known prior art is reliable in operation. There is the drawback, however, that the necessary precise matching of the press basket with the strainer basket involves high manufacturing requirements making these screw separators complex and expensive. Moreover the strainer basket and the press basket wear out rather quickly in operation.
It is therefore the object of the present invention to provide an improved screw separator which operates reliably and which is subjected to reduced wear while the quality is maintained or even improved.